I am not having any problem with you. I do not see us having a fight, just a conversation. :-)

BMR is *BASE* Metabolic Rate. That is, how much you burn if you hold perfectly still all day. The average number difference (number difference on a chart) gets smaller if you add in their activity calories.

BMR charts can be wildly inaccurate in both directions. Plus, as cactus pointed out, BMR is what you need to survive if lying in bed all day. Then the "activity multiplier" gets added on to BMR which can be a very subjective process. One person thinks "moderately active" means going for a walk once in a while but someone else thinks it means Crossfit 5X/week.

Even if you take two people of the same exact height and weight, and basic musculature, doing the same exact activities every day... they CAN have very different metabolisms.
That's just the breaks.
One of them might start gaining weight at 2200 calories...
The other could eat 3000 with impunity.

Such is life.
I know some people don't like to believe that it's true. But it is.
And that's why BMR charts are so inaccurate... they are just guesses as to where a person might be on the average metabolism scale which is more of a bell curve like any measurement of averages in humans.

“You have your way. I have my way. As for the right way, the correct way, and the only way, it does not exist.”
~Friedrich Nietzsche
And that's why I'm here eating HFLC Primal/Paleo.

But their eating double the calories i just done a quick calculation using BMR and it calculated 1711 calories they are having at least double that. That means the whole BRM thing is wrong also maybe.

Anyway I'm not trying to be a know all here, i'm just asking a question.

BMR is only enough to keep you alive if all you did was lay in bed all day and have a ventilator do your breathing for you. You have to calculate in their TDE (total daile expenditure).
Nevermind PB beat me to it

As I understand it, there are (at least) two types (or locations) of insulin monitoring, the liver and the fat cell. When the liver detects low insulin, more insulin is produced. When the fat cell detects low insulin, fat is released. Therefore,

1. When insulin resistance is much higher in the liver than the fat cell, excess insulin will be produced, driving fat into storage and the fat cell won't fight back.
2. When insulin resistance is much higher in the fat cells than in the liver, some level of insulin will still be produced, but the fat cells won't respond well, and won't store excess fat (this needs a protein called asp as well).
3. Most people hit stasis/balance at some point in between "audrey hepburn" and "Guinness book of records".

Or why don't the skinny people become insulin resistant if they are always eating sugary foods and there blood sugar is always high - meaning their insulin is working overtime?

I think that's where you're getting lost. Skinny people CAN be insulin resistant. If fat cells are insulin resistant, the blood glucose just hangs out in their bloodstream, causing all sorts of damage (glycation). In most people, a fair amount of fat gain occurs before fat cells become resistant to insulin telling them to store more, but in other people this threshold is apparently much lower. I remember seeing a study that talked about non-alcoholic fatty liver disease in normal weight subjects, but I can't find a link at the moment.